Combination exhalation valve and speaking diaphragm



J. P. LYTLE ETAL 3,035,574

2 Sheets-Sheet 1 :50 PAUL FI ERIC K604 BY M COMBINATION EXHALATION VALVE AND SPEAKING DIAPHRAGM May 22, 1962 Filed Jan. 21, 1959 i In May 22, 1962 J. P. LYTLE EI'AL 3,035,574

COMBINATION EXHALATION VALVE AND SPEAKING DIAPHRAGM Filed Jan. 21, 1959 2 Sheets-Sheet 2 INVENTOR. HIV ALYTLE an. l/L F'. ER/CKSOIV Patented May 22, 1 362 3,035,574 COMBINATION EXI-IALATION VALVE AND SPEAKING DIAPHRAGM John P. Lytle, Pittsburgh, and Paul F. Erickson, Irwin, Pa., assignors to Mine Safety Appliance Company, Pittsburgh, Pa., a corporation of Pennsylvania Filed Jan. 21, 1959, Ser. No. 788,076 Claims. (Cl. 128-141) This invention relates to masks used with breathing apparatus, and more particularly to the exhalation valves and speaking diaphragms incorporated in such masks.

Practically all breathing apparatus masks have exhalation valves that close during inhalation. Some masks have also been provided with speaking diaphragms. Such a diaphragm is associated with an opening in a mask so that the diaphragm will vibrate as the wearer of the mask speaks, thereby transmitting his speech to the surrounding atmosphere. This makes it much easier to hear and understand the man than if no such diaphragm is present.

It is among the objects of this invention to provide an exhalation valve and speaking diaphragm which are combined into a single unit, which require only a single opening in a mask for their attachment to it, and which are simple and inexpensive in construction.

In accordance with this invention, a tubular holder is adapted to be coupled at one end to the outlet of a mask. The opposite end of the holder is covered by a speaking diaphragm. The holder also is provided with a plurality of circumferentially spaced outlet ports, the o iter ends of which are normally covered by check valve means carried by the holder. Preferably, the holder includes a cup having a base provided with a central inlet joined to a tubular coupling. The outlet ports are in the base around the coupling, and are closed by a flexible annular flap surrounding the coupling.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which FIG. 1 is a fragmentary vertical section through a mask and our combination exhalation valve and speaking diaphragm unit;

FIGS. 2 and 3 are vertical cross sections taken on the lines ll-ll and lillll, respectively, of FIG. 1; and

FIG. 4 is a fragmentary vertical longitudinal section through a modification of the valve and diaphragm.

Referring to FIGS. 1 and 3 of the drawings, a mask 1 of any suitable construction is provided in front of the chin-receiving area with an outlet opening 2. for exhalation. This opening is encircled by an outwardly projecting flange 3 that surrounds the inner end of atubular holder. The holder preferably includes a cylindrical coupling 4 that projects from the mask. The outer end of the coupling may be joined to the base of a shallow cup 5 that is provided with a central inlet 6 coaxial with the coupling.

The cup base also is provided around its central opening with a plurality of circumferentially spaced outlet ports 7. The outer or rear ends of these ports are normally covered by a flexible annular flap 8 that surrounds coupling 4. Most suitably, the flap is the flange portion of a valve member that has a tubular portion 9 fitting snugly around the coupling and spacing it from the encircling outlet flange 3 of the mask. The outlet flange and the tubular members inside of it are all clamped tightly together by a metal band 10 encircling the flange. To help hold the valve member in correct position on coupling 4, the latter is encircled by a rib 11 that fits snugly in a groove 12 in the inner surface of the tubular portion 9 of the valve member. The resistance of valve flap 8 to moving away from and back toward the outlet ports is reduced to a minimum by connecting it to the tubular portion of the valve member by means of a narrow, highly flexible annular portion 13 near its inner diameter.

Air exhaled into the cup leaves it through outlet ports 7, because the front of the cup is covered by a diaphragm. This thin impervious diaphragm 15 is preferably clamped between a pair of perforated baffle plates is and 17. The central areas of these plates are bowed away from each other and the diaphragm so that they will not interfere with the vibrations of the latter. The marginal areas of the plates, however, are clamped together, with the edge of the diaphragm pinched between them, by folding the outer edge of one of the plates around the outer edge of the other plate. One side of these joined edges of the plates engages a gasket 18 seated in a shallow recess 19 in the outer end of the cup. Their opposite side is engaged by a spacing member 2%, the outer surface of which is engaged by a guard screen 21 that extends across the outer baflle plate. All of these members are clamped together by a clamping ring 22 that has a flange 23 overlapping the marginal area of the guard screen. The ring is screwed onto the externally threaded cup 5.

To prevent anything inserted in the perforations 24 in the guard screen from passing through the holes 25 in the outer baffle plate and thereby perforating the diaphragm, the screen is so positioned that its perforations will not be in line with those in the baffle plate, as shown in FIG. 2. This relation is established and preserved by providing the central portion of the outer baflle plate with several outwardly extending detents 26 that project into small holes 27 in the guard screen.

It will be seen that with this invention a single unit contains both the exhalation valve and the speaking diaphragm, so there needs to be only one outlet from the mask connecting with both. It also simplifies construction, because the same cup that holds the diaphragm serves also as part of the valve.

In the modification shown in FIG. 4, the spacer 20 that was required between the baflle plates and the guard screen in PEG. 1 is unnecessary, because the marginal area of the screen 33 has been turned backward and provided with a flange 31 that engages the edge of the outer baflle plate 32. The flange 33 on the clamping ring 34 engages the guard screen flange. This construction eliminates one element that was required by the unit shown in FiG. 1.

According to the provisions of the patent statutes, we have explained the principle of our invention and have illustrated and described What we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

We claim:

1. A combination exhalation valve and speaking diaphragm unit for a mask outlet, comprising a cup having a base and an open side, a speaking diaphragm covering the open side of the cup, said base being provided with a central inlet and with outlet ports surrounding the inlet, a tubular inlet coupling joined to the base around said central inlet, and a flexible annular flap surrounding said coupling and normally covering said ports.

2. A combination exhalation valve and speaking diaphragm unit for a mask outlet, comprising a cup having a base and an open side, a speaking diaphragm covering the open side of the cup, said base being provided with a central inlet surrounded by outlet ports, a tubular inlet coupling joined to the base around said central inlet, and a valve member having a tubular portion mounted on said coupling and having a flexible flange portion normally covering said ports.

3. A combination exhalation valve and speaking diaphragm unit for a mask outlet, comprising a cup having a base and an open side, a speaking diaphragm covering the open side of the cup, said base being provided with a central inlet surrounded by outlet ports, a tubular inlet coupling joined to the base around said central inlet the coupling being surrounded by a rib, and a valve member provided with a tubular portion surrounding said coupling and having an internal groove snugly receiving said rib, the valve member also having a flexible radial flange at one end of said tubular portion normally covering said ports.

4. A combination exhalation valve and speaking diaphragm unit for a mask outlet, comprising a cup having a base and an open side, a pair of perforated bafile plates joined together around their edges and having their central areas spaced apart, a speaking diaphragm disposed between said plates with its marginal area clamped between them, a gasket disposed against the cup around its open side, means clamping said plates against the gasket, said cup base being provided with a central inlet surrounded by outlet ports, a tubular inlet coupling joined to the base around said central inlet, and a flexible annular flap surrounding said coupling and normally covering said ports.

5. A combination exhalation valve and speaking diaphragm unit for a mask outlet, comprising a cup having a base and an open side, a pair of perforated baflie plates joined together around their edges and having their central areas spaced apart, a speaking diaphragm disposed between said plates with its marginal area clamped between them, a gasket disposed against the cup around its open Side and spacing the plates from the cup, a periorated guard plate extending across the bafile plates at the side opposite the cup, a clamping ring screwed onto the cup and having a flange overlapping the marginal area of the guard plate and holding it and the baffle plates in place, said cup base being provided with a central inlet surrounded by outlet ports, a tubular inlet coupling joined to the base around said central inlet, and a flexible annular flap surrounding said coupling and normally covering said ports.

References Cited in the tile of this patent UNITED STATES PATENTS 1,730,227 McBride Oct. 1, 1929 2,684,066 Glidden July 20, 1954 FOREIGN PATENTS 150,232 Great Britain Sept. 2, 1920 566,088 Great Britain Dec. 13, 1944 572,888 Great Britain Oct. 29, 1945 1,011,732 Germany July 4, 1957 (Kl.61a) 

